This disclosure relates to devices suitable to receive and enclose a biological sample for long term cryogenic storage. Cryogenic storage is often used for the purpose of halting biological activity in cells such that a biological sample can be stored in situations where it is not possible or convenient to manipulate the sample at the present time. For example, in situations where patients are undergoing in vitro fertilization procedures, oocytes are often harvested from a patient who has undergone hormone treatment to cause their ovaries to produce a larger number of follicles and oocytes that normally produced during a typical cycle. While the hormone therapy is needed to stimulate the production of multiple oocytes, the same hormone therapy often causes side affects to the patient's uterine tissue or other portions of their reproductive tissue that minimizes the chances of successful embryo implantation into the patient during the same cycle.
Accordingly, it is often desired to fertilize oocytes to create embryos at the time they are harvested and cryogenically store them for implantation during a future cycle. In other situations it is desirable for female patients to cryogenically store harvested and unfertilized oocytes for potential future use. Other types of biological tissue is often desired to be stored on a long term basis for future research or therapeutic purposes, such as muscle tissue. Biological samples to be cryogenically stored are stored with vitrification media that is used to prepare the sample for long term storage, which may include removing water from the sample. It is known that the vitrification media is harmful to the biological sample at room temperature so it is desired to minimize the time that the biological sample is at room temperature in the presence of vitrification media.
A first representative embodiment of the disclosure provides a method of cryogenically preserving biological material. The method includes the steps of providing a first elongate member with a trough disposed upon an outer surface of the first elongate member, and a first bulge coaxially defined upon the outer surface with an outer diameter of the first bulge larger than an outer diameter of the first member. A biological material is deposited upon the trough. The method further includes the step of sliding an elongate second member over the first member to form a preservation assembly. The second member has an inner diameter substantially the same as the outer diameter of the first bulge such that an inner surface of the second member makes substantially continuous contact around the circumference of the bulge portion. The method further includes the step of depositing the preservation assembly within a cryogenic medium.
A second representative embodiment of the disclosure provides a cryopreservation device for storing reproductive biological material configured to receive a biological sample for long term cryogenic storage. The device includes an elongate first member extending between a distal end and a proximal end and a first bulge portion disposed around a circumference of the first member, and a trough defined within the first member. A second member with a lumen is defined therethrough, the second member is configured to slide over the first member, the inner diameter of the second member being substantially the same as an outer diameter of the bulge portion to form a seal between the first and second members.
A third representative embodiment of the disclosure provides a cryopreservation device for storing reproductive biological material configured to receive a biological sample for long term storage. The device includes an elongate first member extending between a distal end and a proximal end and a first bulge portion disposed around a circumference of the first member upon the distal end, and a trough defined within the first member. The proximal end of the first member comprises a flared portion that includes an increasing outer diameter along the length thereof in a direction extending away from the trough. A second member with a lumen is defined therethrough, the second member is configured to slide over the first member, the inner diameter of the second member being substantially the same as an outer diameter of the bulge portion to form a seal between the first and second members.
Advantages of the present disclosure will become more apparent to those skilled in the art from the following description of the preferred embodiments of the disclosure that have been shown and described by way of illustration. As will be realized, the disclosed subject matter is capable of other and different embodiments, and its details are capable of modification in various respects. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive.
Turning now to
The device 10 includes an elongate shuttle 20 and an elongate sheath 60 that may be slidably disposed over the outer surface of the shuttle 20. The sheath 20 may be an elongate rod that extends between a distal end portion 24 and a proximal end portion 22 with a longitudinal axis 20a disposed therethrough. The shuttle 20 further includes a trough 40 that provides a portion of the outer surface of the shuttle 20 that extends within the cylindrical surface that forms the majority of the outer surface of the shuttle 20. The trough 40 may include a bottom surface 42 that is configured to receive a biological sample M (such as a reproductive biological sample, e.g. embryo or oocyte in a drop with vitrification media, or such as other types of cellular material suitable for long term storage, such as muscle tissue and the like) (
In some embodiments, the two end surfaces 44 of the trough 40 may be disposed at an acute angle, such as about 45 degrees, with respect to the longitudinal axis 20a of the shuttle 20. The formation of acute end surfaces 44 allows for ease of manipulating a biological sample M positioned proximate one end of the bottom surface 42 because it allows an oblique angle of attack to position the biological sample M with tweezers, a needle, pipet, or other suitable instrument appropriate for manipulating the biological sample M.
The trough 40 may be configured to receive a reproductive biological sample M thereon, such as a fertilized embryo that is embedded in a drop of vitrification media, or an oocyte that may be embedded in suitable vitrification media. A typical reproductive biological sample M may have a volume of 0.5 micro liters, which has a nominal diameter of about 0.5 mm (0.02 inches). to about 1 mm (0.04 inches). In some embodiments, the trough 40 is configured such that a nominally sized biological sample M may be disposed upon the trough 40 with the upper surface of the biological sample M (i.e. the point(s) upon the biological sample M that is furthest away from the bottom surface 42 of the trough 40) below the outer surface of the shuttle 20. In other words, the trough 40 is configured such that a nominal sample M completely fits within the void created within the trough 40. In other embodiments, the trough 40 may be oriented such that the outer surface (as defined above) of the biological sample M is disposed below the central portion 32 of the bulge portion 30 (discussed in detail below). In still other embodiments, the trough 40 is configured such that an upper surface of a nominal biological sample M is disposed below the inner diameter of the end portions 65, 66 of the sheath 60. In the these embodiments, the trough 40 is configured such that a nominal biological sample M placed thereon is not disturbed when the sheath 60 is initially slid over and removed from the shuttle 20.
The shuttle 20 additionally includes two or more bulge portions 30 that are disposed upon the outer circumferential surface of the shuttle 20. The bulge portions 30 each include an outer diameter that is slightly larger than the outer diameter of neighboring portion of the shuttle 20, and in some embodiments, the outer diameter of the remaining portions of the shuttle 20. In some embodiments, the bulge portion 30 may include an arcuate outer profile from one side of the bulge to the other, such that a central portion 32 of the bulge portion 30 has a larger outer diameter than side portions 34 on opposite sides of the central portion 32. In some embodiments, the outer profile of the bulge portion 30 is the same around the entire circumferential surface of the shuttle 20. In other embodiments, the outer profile of the bulge portion 30 varies around the circumference of the shuttle 20.
In some embodiments the two bulge portions 30 are disposed with the same size and shape while in other embodiments the opposite bulge portions 30 may have differing sizes and/or shapes. In some embodiments, a single bulge portion 30 may be disposed upon the shuttle on each side of the trough 40, while in other embodiments shown in
The bulge portions 30 may be formed monolithically with the remainder of the shuttle 20, while in other embodiments, the bulge portion 30 may be a separate component from the shuttle 20 that is fixed thereto, either through friction or snap fit, adhesive, or by otherwise mechanically fixing thereto. In embodiments where the bulge 30 is a separate component from the shuttle 20, the bulge 30 may be one or more o-rings that are received upon the outer surface of the shuttle 20, or within an arcuate slot defined upon the surface of the shuttle 20. In some embodiments, the shuttle 20 (with or without the handle 80) including the trough 40 and bulge portions 30 is a single molded piece, or may be machined, or otherwise formed from a single stock of material.
In some embodiments, the shuttle 20 may be about 5 inches long, or within a range (and inclusive of the lengths within the range) of about 3 to about 7 inches, or other appropriate lengths (either inclusive of a handle 80 fixed to the proximal tip 22a of the shuttle 20, or exclusive of the length of the handle 80). The length of the shuttle 20 may be configured to be long enough to be easily manipulated by the user, easy to identify and manipulate when placed within a liquid nitrogen bath (or other cryogenic liquid or cryogenic container), and provide a suitably sized trough 40 for receipt of a biological sample M thereon.
The shuttle 20 may have an outer diameter W (
The bulge portions 30 are configured with an outer diameter, or at least a portion with an outer diameter at least slightly larger than the outer diameter than the remainder of the shuttle 20. Similarly, in some embodiments, the outer diameter (or at least the largest outer diameter) of the bulge portion 30 may be substantially the same as the inner diameter of the sheath 60. As discussed below, in embodiments where the sheath 60 is formed from both a central shape memory portion 64 and first and second substantially flexible end portions 65, 66 on opposite sides of the central portion 64, the inner diameter of the central portion 64 may be slightly larger than the largest outer diameter of the bulge portion 30, while the inner diameter of the end portions 65, 66 may be substantially the same as, or in other embodiments slightly smaller than, the largest outer diameter of the bulge portion 30. In a first exemplary embodiment where the diameter of the shuttle 20 is 0.068 inches, the outer diameter of the bulge portions 30 (or the largest outer diameter of the bulge portions 30) is 0.088 inches, and in another embodiment the largest outer diameter of the bulge portion is 0.079 inches. In some embodiments, the shuttle 20 may be made from PEEK (polyether ether ketone) or other plastic or thermoplastic.
The sheath 60 is an elongate member that extends from a distal end 61 to a proximal end 62 with a lumen 68 disposed therethrough. The sheath 60 is configured to slide over the shuttle 20 coaxially. As mentioned above, the inner diameter of the lumen 68, or at least a portion of the lumen 68 is substantially the same, or in some embodiments slightly smaller than the outer diameter of the bulge portion 30. Specifically, in some embodiments, the inner diameter of each of the first and second ends 65, 66 may be less than the inner diameter of the central portion 64, and the inner diameter of each or one of the first and second ends 65, 66 may be less than at least the largest outer diameter of the bulge portion 30.
In some embodiments, the sheath 60 may be formed with a central portion 64 and opposite end portions 65, 66. The central portion 64 may be made from a shape memory material, such as Nitinol. The central portion 64 may be substantially tubular in its memorized austenite orientation and configured with an inner diameter just larger than the largest outer diameter of the bulge portion 30 such that the central portion 64 of the sheath 60 can easily slide over the shuttle 20. The shape memory material or alloy selected may be one with a martensite to austenite transition temperature located at about room temperature (e.g. 70-75 degrees). In other embodiments, the alloy may be selected to have a transition temperature at a temperature above normal room temperature but below normal body temperature. Pending U.S. Published Application Number 2009/0123992 titled “Shape Shifting Vitrification Device” issued as U.S. patent Ser. No. ______ includes a description of the operation of shape memory materials, such as Nitinol, and the application is hereby fully incorporated by reference herein.
The sheath 60 may be configured such that the central portion 64 is disposed in registry with the trough 40 of the shuttle 20 when the sheath 60 is slid over and aligned with the shuttle 20. In embodiments shown in
As discussed below, the registration between the central portion 64 and the trough 40, along with markings that may be provided upon the outer surface of the central portion 64, allows precise crimping or otherwise inward deformation such that the inner surface of the central portion 64 contacts the biological sample M disposed upon the bottom surface 42 of the trough 40. The deformation of the central portion 64 and contact with the biological sample M allows direct conduction heat transfer between the biological sample M and the central portion 64, which provides for extremely rapid cool down of the biological sample M and device 10 when the device 10 is cooled in a cryogenic bath, and extremely rapid heat up of the sample M and the device 10 when the device 10 is placed in a warming bath. A detailed description of the process of crimping a portion similar to the central portion 64 is found in the U.S. 2009/0123992 published application. The placement of the sheath 60 over and in registration with the shuttle 20 establishes the preservation assembly.
In some embodiments, tweezers may be used to crimp or deform the central portion inwardly, and in some embodiments, metered tweezers or pliers, i.e. devices with two opposed jaws that are configured to be moved to a position with the tips of the jaws a specific distance apart but not touch, may be used to crimp the central portion 64 to a specific geometry that allows contact with a range of potential sizes of biological samples but prevents contact between the central portion 64 and the shuttle 20 (which could damage the shuttle 20) may be used.
The inner surface of the central portion 64 (and potentially the inner surface of the end portions 65, 66) may be hydrophobic (either intrinsically hydrophobic or coated with a hydrophobic material) to prevent the biological sample M from sticking to the inner surface of the sheath 60. Hydrophobic coatings such as polytetrafluoroethylene or polyxylene polymer may be applied to the inner surface of the central portion 64. FEP, which may be used to make the first and second end portions 65, 66 is hydrophobic. In embodiments where the first and second end portions 65, 66 are made from other plastics or other flexible materials, the inner surface thereof may have a hydrophobic coating.
The first and second end portions 65, 66 of the sheath 60 are each fixed to opposite ends of the central member 64. The first and second ends 65, 66 may be made from a relatively flexible material, such as FEP (Fluorinated ethylene propylene) or other flexible materials that are configured to withstand the very low cryogenic temperatures as well as tolerate the rapid cool down and heat up rates as the device 10 is placed in a cryogenic fluid as well as a warming bath. The materials are also configured to expand and contract about the same amount as the material chosen for the shuttle 20 during the large thermal changes associated with vitrification and subsequent return to the warmed temperature. The material chosen for the end portions 65, 66 of the sheath 60 preferably has a lower durometer than the material chosen for the shuttle 20, such that the end portions 65, 66 of the sheath 60 deform when the sheath 60 engages the shuttle 20.
The first and second ends 65, 66 of the sheath 60 may be fixed to opposite ends of the central portion 64 with adhesive, with a crimped connection, or with other connection methods known in the art. In some embodiments best shown in
The first and second ends 65, 66 are configured to be sufficiently flexible around room temperature to allow sheath 60 to slide over the shuttle 20, even in embodiments wherein the inner diameter of the first and second ends 65, 66 is slightly smaller than at least the largest outer diameter of the bulge portion 30. The radial expansion of the sheath 60 over the bulge portion 30 causes a tight seal between the respective end portion 65, 66 and the respective bulge 30 around the circumference of the shuttle 20, which prevents passage of fluid therebetween. The end portions 65, 66 of the sheath 60 are configured to be sufficiently flexible to allow the user to slide the sheath 60 over the shuttle 20 with one of their hands, while the user holds the shuttle 20 steady in their other hand.
In some embodiments best shown in
In some embodiments specifically shown in
In use, a biological sample M is disposed upon the bottom surface 42 of the trough 40. Upon placement of the biological sample, the professional slides the sheath 60 coaxially over the shuttle 20 until the central portion 64 of the shuttle 60 is in registry with the trough 40. As the sheath 60 is slid over the shuttle 20, the first and second ends 65, 66 are expanded outward as they pass over the bulge portions 30 disposed upon the shuttle 20. Specifically, as can be appreciated with reference to
As the sheath 60 is continued to be pulled over the shuttle 20, the proximal end 65 clears the distal bulge 30 such that the central member 64 is disposed over the distal bulge 30. With additional movement in the same direction, the proximal end 65 of the sheath 60 encounters the proximal bulge 30 and the distal end 66 encounters the distal bulge 30a. The respective bulges 30 urge outward expansion of the respective end portion 65, 66 to allow the sheath 60 to be pulled over the shuttle 20. The tight fit between the shuttle 20 and sheath 60 at the bulge portions 300a and the forced expansion of the first and second ends 65, 66 of the second member cause surface to surface contact between the bulges 30 and the end portions of the sheath 60 around substantially the entire outer circumference of the respective bulge 30, which substantially prevents fluid flow between the respective bulge 30 and the inner surface of the sheath 60.
Upon proper alignment of the sheath 60 with respect to the shuttle 20, the central portion 64 of the sheath 60 may be crimped inwardly with tweezers or another tool configured to crimp the surfaces of the central member toward each other. The crimping of the central member 64 establishes surface contact between the biological sample M disposed upon the bottom surface 42 of the trough 40 and the central member 64 to allow for convection heat transfer therebetween, for highly efficient and rapid heat transfer ultimately between the biological sample M and the respective cooling or warming fluid. After the central portion 64 is crimped, the combined shuttle 20 and sheath 60 are dipped or lowered into the cryogenic fluid, such as liquid nitrogen, for long term storage.
As the assembled device 10 is disposed into the cryogenic fluid, the substantially cooler cryogenic fluid rapidly receives heat from the biological sample M through the central portion 64 (and the remainder of the device 10), such that the biological sample M and the device 10 cools to substantially the same temperature as the cryogenic fluid in a very short time period, such as substantially less than one second. The method of assembling the device 10 (i.e. placing the biological sample M upon the bottom surface 42 of the trough 40 and sliding the sheath 60 over the shuttle 20 until the central member 64 is in registry with the trough 40, and then crimping the central member 64) is configured to be performed in a relatively short time period (such as less than 10 seconds) to minimize the amount of time that the biological sample is at normal room temperature in the presence of vitrification media, which may damage the biological sample M if at room temperature for extended time periods. The speed of assembling the device 10 and vitrifying the sample using the device 10 is possible because the device 10 may be assembled without the use of any external tools and without requiring that any of the ends of the device be heat fused. In addition to the time savings, the device 10 does not require heat fusing one or both ends of the device, which if done improperly could damage the device or even the sample if performed improperly, and could also cause personal injury. As discussed below, the ease of assembly of the device 10 (and specifically the ability to assemble the device 10 without requiring external tools or a heat source) allows for receipt of a biological sample M and assembly and placement into cryogenic fluid in a substantially more rapid manner than would be possible with conventional devices where the device must be assembled (and disassembled) with external tools and/or fused with a heat source.
When it is desired to warm the biological sample M for further manipulation or for implantation into a patient, the device 10 is removed from the cryogenic fluid and placed into a warming bath, which may be substantially room temperature or body temperature liquid. The placement of the device 10 within the warming fluid causes rapid heat transfer to the biological sample M through the central portion 64 of the sheath 60, which heats the biological sample M (as well as the remainder of the device 10) to about the temperature of the warming fluid in a rapid manner (such as less than one second for at least the biological sample M). As heat is transferred from the warming fluid to the central member 64 and the biological sample M, the temperature of the central member 64 increases until it reaches and exceeds the transition temperature of the material, which causes the central portion 64 to automatically rebound to its nominal, non-crimped orientation, such that the central portion 64 no longer contacts the biological sample M.
After the device 10 has been disposed within the warming fluid and the central portion 64 rebounds to its nominal position, the device 10 is removed from the warming bath. The user pulls the second cylindrical portion 60 linearly away from the shuttle 20 until the trough 40 is exposed, which allows the user to remove the biological sample M therefrom and process the biological sample M as needed to remove the vitrification media therefrom and process and/or manipulate the biological sample as desired.
Turning now to
The proximal end 122 of the shuttle 120 additionally includes a flared portion 126 disposed on the side of the trough 40 from the bulge 30. The flared portion 126 includes an expanding outer diameter from a portion proximate the trough 40 to the proximal end 122. In some embodiments, the flared portion 126 may be linearly expanding, while in other embodiments, the flared portion 126 may expand in other geometries. The flared portion 126 includes a starting end 126a that has an outer diameter less than the inner diameter of the sheath 60, and specifically the first and second end portions 65, 66 of the sheath 60. As an exemplary embodiment, the flared portion 126 of the shuttle 120 may increase from an outer diameter of about 0.068 inches at the starting end 126a to an outer diameter of about 0.082 inches at the extended end 126b (with the inner diameter of the first end portion 65 of the sheath 60 being less than 0.082 inches). In other embodiments, the dimensions of the flared portion 126 of the shuttle 120 and the sheath 60 may be suitable for the desired size of the entire device 10 as well as the size of the biological sample M intended for use with the device 10.
The profile of the flared portion 126 expands along the length of the shuttle 120 to an outer diameter larger than the outer diameter of the first and second end portions 65, 66, such that the respective end portion 65, 66 that extends over the flared portion 126 (as the sheath 60 is slid over the shuttle 120) toward registration between the shuttle 120 and the sheath 60, such that the flared portion 126 causes radial expansion of the sheath 60 and causing surface to surface contact between the sheath 60 and the flared portion 126 of the shuttle 120, which substantially prevents fluid communication between the flared portion 126 and the sheath 60. The shuttle 120 is configured such that the opposite end portion 66 of the sheath 60 engages the bulge portion 30 upon the shuttle 120 as the first end portion 65 of the sheath 60 engages the flared portion 126 to substantially enclose the trough 40 of the device 10. The shuttle 120 may additionally include a handle 80 that is disposed upon the proximal end thereof. In embodiments where the shuttle 120 includes a handle 80, the registry between the shuttle 120 and the sheath 60 may be established when a sufficient frictional connection between the sheath 60 and the flared portion 126 of the shuttle 120 is established to prevent further linear motion of the sheath 60 with respect to the shuttle 120. In other embodiments, the sheath 60 may be in registry with the shuttle 120 when the tip of the sheath 60 contacts a step 82 between the proximal end of the shuttle 120 and the handle 80.
In use, the device using the shuttle 120 is assembled after the user places a biological specimen M upon the trough 40 and the sheath 60 is slidably disposed about the shuttle 120. Specifically, the first end 65 of the sheath 60 is placed over the distal end 124 of the shuttle 120 that includes the bulge 30 such that the first end 65 of the sheath 60 is stretched outwardly over the bulge portion 30 with continued linear movement. As the user continues sliding the sheath 60 over the shuttle 120, the first end 65 passes over the trough 40 and with continued translation slides over the proximal end portion 122 of the shuttle 120 until the first portion 65 encounters the flared portion 126. With motion of the first end 65 of the sheath 60 over the flared portion 126, the flared portion 126 urges outward radial expansion of the sheath 60, which increases the friction between the two components and the tightness of the surface to surface contact therebetween.
With sufficient motion of the sheath 60 with respect to the shuttle 120, a substantially leak tight connection is established between the sheath 60 and the flared portion 126. With the connection between the sheath 60 and the flared portion 126 established, the central portion 60 of the sheath 60 is disposed in registry with the trough 40 to allow subsequent crimping or deformation of the central portion 64 for surface contact between the central portion 64 and the biological sample M for conductive heat transfer therebetween. Similarly, as the sheath 60 is positioned with respect to the shuttle, the second end 66 of the sheath 60 contacts and is expanded by the bulge portion 30 to establish tight surface to surface contact therebetween to substantially prevent fluid communication therebetween, therefore isolating the trough 40. With the sheath 60 disposed in registry with the shuttle 120, the central portion 64 may be crimped with respect to the shuttle 120, and vitrified and cooled as discussed above with respect to the device 10.
While the preferred embodiments of the disclosure have been described, it should be understood that the disclosure is not so limited and modifications may be made without departing from the disclosure. The scope of the invention is defined by the appended claims, and all devices that come within the meaning of the claims, either literally or by equivalence, are intended to be embraced therein.
This application claims priority from U.S. Provisional Application No. 61/332,005, filed on May 6, 2010, the entirety thereof is hereby full incorporated by reference herein.
Number | Date | Country | |
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61332005 | May 2010 | US |